The materials included in this compilation are for the use of Dwyer Instruments, Inc. potential customers and current employees as a resource only. They may not be reproduced, published, or transmitted electronically for commercial purposes. Furthermore, the Company’s name, likeness, product names, and logos, included within these compilations may not be used without specific, written prior permission from Dwyer Instruments, Inc. ©Copyright 2014 Dwyer Instruments, Inc.

1. Handheld Digital Manometers
The materials included in this compilation are for the use of Dwyer Instruments, Inc. potential customers and current employees
as a resource only. They may not be reproduced, published, or transmitted electronically for commercial purposes.
Furthermore, the Company’s name, likeness, product names, and logos, included within these compilations may not be used
without specific, written prior permission from Dwyer Instruments, Inc. ©Copyright 2014 Dwyer Instruments, Inc.

2. 476A - Information
Low Cost Single Pressure Manometer
Instant selection from up to eight
English/Metric units
Features electronic zeroing
Extruded Aluminum Case
Operates on a 9V Battery
for 100Hrs

3. 476A - Specifications
Display: 4 digit LCD
Temperature Limits: -17.8 to 60°C
Pressure Accuracy: ±1.5% FS
Pressure Limit: 0.34 Bar
Designed especially for the HVAC contractor, the Model
476A-0 can be used to set gas supply pressures, verify
pressure switch operation, adjust regulators, check
pneumatic systems and computer peripherals.

4. 478A - Information
Low cost differential pressure
manometer
Instant selection from up to
nine English/Metric units
Stores minimum and
maximum readings since last
power cycle

5. 478A - Specifications
Display: 4 digit LCD
Temperature Limits: -17.8 to 60°C
Pressure Limits: 0.34 Bar
Pressure Accuracy: ±1.5% FS
Operates on a 9V Battery
for 100Hrs
Housing Material: Extruded
Aluminum

6. 478A - Specifications
The Series 478A manometer can be
used to measure positive, negative,
or differential pressures. The unit
features selectable units, auto zero,
hold and a Min/Max function. Press
the Hold key to freeze the current
pressure measurement on the
display. The 478A manometer
includes a zeroing button to null out
any minor pressure differences.

7. 478A - Specifications
Display: 4 digit LCD
Temperature Limits: -17.8 to 60°C
Pressure Limits: 0.34 Bar
Pressure Accuracy: ±1.5% FS
Operates on a 9V Battery
for 100Hrs
Housing Material: Extruded
Aluminum

8. 475 -X-FM- Information
Intrinsically Safe Differential
Pressure Manometer ( Factory
Mutual approved)
Ranges down to 0 to 0.249 KPa
Selection of KPa or in w.c. for
engineering units
Features electronic zero
Metal barbed fittings

9. 475 - Specifications
Display: 4 Digit LCD
Temperature Limits: -17.8 to 60°C
Pressure Limits: 0.74 Bar to 13.79 Bar (range
dependent)
Pressure Accuracy: 0.5% FS
Operates on a 9V Battery
for 100Hrs
Housing Material: Extruded Aluminum
Weight: 306 g

10. 477AV - Information
Full - featured differential pressure
manometer with integral air velocity/air
flow calculations
Ranges as low as 0 to 249 Pa
Instant selection of up to 9 English /
Metric units
Stores up to 40 readings in internal
memory
Features Backlighting and electronic
zeroing

11. 477AV - Specifications
Display: 4 digit LCD
Temperature Limits: 0 to 60°C
Pressure Accuracy: ±0.5% Full Scale
Operates on a 9V Battery
for 100Hrs
Internal Memory: up to 40 readings
Weight: 289 g

12. 477AV – Purpose
Packed with features needed to make pressure
measurements and recording faster, easier and
more accurate than ever.
The memory function enables storage of up to
40 readings - perfect for HVAC technicians
making Pitot tube traverses of air flow readings
across a duct.
The 477A is also ideal for maintenance
personnel or technicians that require a highly
accurate standard to check their
instrumentation or equipment to ensure proper
performance

13. 477B - Information
Contains a highly accurate differential pressure
sensor
Accuracy: 0.1% Full Scale
Instant selection from up to nine
English/Metric units
Features a backlight and electronic zeroing

14. 477B - Specifications
Display: 0.42 inch 4 digit LCD
Temperature Limits: 0 to 40°C
Pressure Accuracy: ±0.1% FS
Operates on a 9V Battery
for 100Hrs
Stores up to 40 readings
Weight: 289 g

15. 490A - Information
Wet / wet differential pressure
transmitter with 316L Stainless Steel
wetted parts
Ranges up to 35.5 Bar (max pressure
up to 68.95 Bar)
Instant selection from up to eight
English/Metric units
Visual and audible overpressure alerts

16. 490A - Specifications
Display: 4 digit LCD
Temperature Limits: 0 to 60°C
Pressure Accuracy ±0.5% Full Scale
Operates on a 9V Battery for 100Hrs
Internal Memory: Stores up to 40 readings
New feature: Series 490 is a field adjustable damping.
This allows the user to choose the level of display
averaging rate corresponding to the fluctuation level
common in many applications.

17. Magnehelic – New Accessories
Two new Magnehelic options
-AHU1- Flush mounted bracket installed on
Magnehelic
-AHU2- Flush mounted bracket installed on
Magnehelic with A-481 Installer Kit